SAN FRANCISCO— The National Marine Fisheries Service today proposed regulations under section 4(d) of the Endangered Species Act to protect the southern population of green sturgeon from “take” and other harmful activities. These take prohibitions would make it unlawful to kill or harm southern green sturgeon and could require changes in operations of dams and water diversions, commercial and recreational fisheries, dredging operations, and pesticide applications to protect the green sturgeon, an imperiled migratory fish that has survived since the Pleistocene.

“We strongly support the proposed take regulations, which are urgently needed to ensure rare green sturgeon are not killed or harmed by water projects, overfishing, or pesticides,” said Jeff Miller, a conservation advocate with the Center for Biological Diversity. “Recent surveys have shown some of the lowest recorded numbers of spawning green sturgeon in the Sacramento River. With so few southern sturgeon left and the San Francisco Bay-Delta food web they depend upon unraveling, comprehensive protection from take is critical for the recovery of this ancient fish.”

The proposed 4(d) rule would prohibit all unauthorized “take” of southern green sturgeon throughout their spawning and rearing range in the Sacramento, Feather, and lower Yuba rivers, the Sacramento-San Joaquin Delta and San Francisco Bay, and coastal rivers, estuaries, and marine waters inhabited by sturgeon throughout California, Oregon, and Washington. ‘‘Take’’ includes killing, injuring, harassment, hunting, capture, or collecting, as well as harm from significant habitat modification or degradation that impairs breeding, spawning, rearing, migrating, feeding, or sheltering. Exemptions would allow for tribal fisheries, scientific research and monitoring activities, emergency rescue and salvage activities, and habitat restoration projects.

The rule discusses specific activities likely to take or harm green sturgeon, including commercial and recreational fisheries, habitat-altering activities, impeded migration from dams and water diversions, entrainment during water diversions or dredging, application of pesticides and pollutants, and nonnative species introductions.

In order to comply with the 4(d) rule, state commercial and recreational fisheries would have to submit a Fisheries Management and Evaluation Plan to theFisheries Service that prohibits retention of green sturgeon (zero bag limit), includes measures to minimize incidental take of green sturgeon, and ensures the fishery will not significantly reduce the likelihood of survival or recovery of the southern sturgeon population. In 2007, California and Washington revised fishing regulations to prohibit retention of green sturgeon, and Oregon prohibited retention of green sturgeon in lower Columbia River recreational fisheries. For commercial fisheries, the retention of green sturgeon has been prohibited in the Columbia River since 2006 and statewide in Washington since 2007. California has prohibited commercial fishing for sturgeon since 1917.

American Indian fisheries for green sturgeon would be required to develop tribal resource-management plans for the fish. The only tribal take of southern green sturgeon is as bycatch in salmon and white sturgeon fisheries conducted by the Quinault Tribe in coastal Washington waters. In 2006 the Quinault implemented zero retention of green sturgeon for their Grays Harbor fishery. The Yurok and Hoopa tribes harvest green sturgeon in the Klamath River in California, but most fish are believed to be from the northern population, which is not federally protected. Overall, the take of green sturgeon in tribal fisheries has been low compared to non-tribal fisheries.

In response to a 2001 Center listing petition and a subsequent lawsuit, the Fisheries Service in 2006 listed the southern green sturgeon population — fish in the San Francisco Bay and Delta that spawn in the Sacramento River basin, but migrate along much of the west coast from Mexico to Canada — as a threatened species under the Endangered Species Act. In September 2008 the Fisheries Service proposed designating areas of river, estuarine, bay, and coastal marine habitats in California, Oregon, and Washington as critical habitat for the southern population of green sturgeon. The proposal included 325 miles of freshwater-river spawning habitat in the Sacramento, lower Feather, and lower Yuba rivers; more than 1,000 square miles of estuarine and bay habitats in the Sacramento-San Joaquin Delta and other bays and estuaries in California, Oregon, and Washington; and almost 12,000 square miles of coastal marine habitat from Monterey Bay, Calif., to Cape Flattery, Wash.

The green sturgeon, Acipenser medirostris, is one of the most ancient fish species in the world, remaining unchanged in appearance since it first emerged 200 million years ago. Green sturgeon are among the largest and longest-living fish species found in freshwater, living up to 70 years, reaching 7.5 feet in length, and weighing up to 350 pounds. Sturgeon have a prehistoric appearance, with a skeleton consisting of mostly cartilage and rows of bony plates for scales. They have snouts like shovels and mouths like vacuum cleaners that are used to siphon shrimp and other food from sandy depths.

Like salmon, sturgeon are anadromous, migrating to the ocean and returning to freshwater to spawn. Only three known spawning grounds remain, in the Sacramento and Klamath rivers in California and the Rogue River in Oregon. Between four and seven spawning populations have already been eliminated in California and Oregon. The estimated abundance of green sturgeon in the Sacramento River plummeted by 95 percent between 2001 and 2006. Severe declines in both green and white sturgeon come as scientists have documented the collapse of other fish species in the Sacramento-San Joaquin Delta, such as delta smelt, longfin smelt, Sacramento splittail, threadfin shad and striped bass, due to the combined effects of Delta water diversions and exports, pesticides and pollution, and impacts of introduced species on the Delta’s planktonic food web. Copepods that sustain the Delta food chain and are a food source for green sturgeon have fallen to the lowest levels ever recorded.